Telegraph key



July 3 31934. R HElNTZ 11,964,916

TELEGRAPH KEY Filed May 1, 1933 INVENTOR, RALPH M. l'lEl/VTZ.

BWK

ATTORNEY Patented July 3, 1934 UNITED STATES PATENT OFFICE TELEGRAPH KEYApplication May 1, 1933, Serial No. 668,778

3 Claims.

My invention relates to telegraph keys and more particularly to a keyadapted for panel mounting, or for use on such panels which are exposedto the elements, the contact points actuated by the key being protectedfrom rain, fog, snow or other moisture.

Among the objects of my invention are: to provide a light and sturdytelegraph key adapted for airplane use; to provide a telegraph key 10which may be conveniently mounted on a vertical panel or bulkhead; toprovide a telegraph key which, when mounted on a panel exposed to theelements, will have its contacts protected from moisture; and to providea simple efficient mulii; tiple contact telegraph key.

Other objects of my invention will be apparent or will be specificallypointed out in the description forming a part of this specification, butI do not limit myself to the embodiment of my invention hereindescribed, as various forms may be adopted within the scope of theclaims.

The advantages of my invention can be most readily understood by adescription of the drawing accompanying and forming a part of thisspecification, of which:

Figure 1 is a top View in elevation of a preferred form of key adaptedto be applied to a vertical panel.

Figure 2 is a side view in elevation of the device.

Figure 3 is a sectional View taken along the line 33 in Figure l, thekey being shown fastened to a panel.

Figure 4 is an elevational view of the device as seen from the front.

Z5 Figure 5 is an elevational view taken from the rear.

In the preferred embodiment illustrated in the drawing, a metal cup, prferably of aluminum or aluminum alloy, is formed with a hollow bodyportion 1 and a rim 2. The outer face 4 of the rim is adapted to fit apanel or bulkhead 5 as shown in Figures 2 and 3, the rim being bored toform threaded holes 6. The panel and rim may then be fastened togetherwith panel screws '7. It is also desirable to cut an aperture in thepanel as large or slightly larger than the cross section of the hollowin the cup body, to allow the passage of the operating arm, which willbe later described.

A metal shaft 9 passes through opposite walls of the hollow bodyportion, and through a. bearing 10 in the end of an operating arm havingan enclosed portion 11 extending out past the rim and thereafterchanging direction to form an oblique angle with the rim and attached tothe panel.

The portion outside of the rim after the arm has changed direction, maybe termed the operating arm extension 12, which terminates at its distalend in an operating button 14, similar to those used on telegraph keysin common use.

I prefer to mill or otherwise form a flat surface 15 parallel with theouter face 4, on the operating arm at the point where the arm changesdirection, drill through the enclosed portion 11 of the arm to the shaft9, tap the hole and insert therein a set screw 16 having a point 17engaging the shaft, and an exposed slotted head 19. I may thereby adjustthe relative position of the arm on the shaft, and lock the two to causerotary motion of the shaft to take place upon actuation of the operatingarm.

The two ends 20-20 of the shaft Which extend outside the cup arepreferably slotted and a fiat contact spring 21 inserted in each andheld in place by pins 22. These springs, of phosphor bronze or similarmaterial, extend in both directions at right angles to the shaft, andsubstantially parallel to the outer face 4. I have shown these springsextending both Ways for substantially equal distances, but the relationof distances on each side of the shaft may be changed to suit conditionsof use.

Inserted in the ends of each contact spring are contact points 24,preferably four in all.

The bottom outside face 25 of the cup is formed i '1 with a slot 26 inwhich is set the crossbar 27 of an H-shaped piece of insulating material29, held in place by a clamp plate 30 tightened by a clamp screw 31passing through the clamp plate and insulating crossbar 2'7 andextending into the bottom of the hollow body portion. The insulatingmaterial cannot turn, as its edges are held by the sides of the slot 26.

The end extensions 32 of the H terminate below the ends of the contactsprings 21 and carry stationary contacts 34 extending toward the contactpoints on the contact springs. The contacts 34 are held in place by nuts35 which also hold connection lugs 36 in place.

The cooperating sets of contact points and contacts are so located thatat one position of the operating arm the upper set of contact pointsmake contact with the upper set of stationary contacts, and theremaining connections are broken, while at another position of the armthe reverse will take place.

I prefer, however, to maintain the upper connections by means of forceexerted by a spring 37 attached at one end to the shaft 9 and at theother to the H-shaped piece of insulating material. One set ofconnections are thus made at all times the key is not operated, thoseconnections being broken, and a second set made when the button 14 isdepressed, the key returning to the original position, and connections,when released.

No adjustments are shown on the key illustrated, as bending the contactsprings will allow any necessary adjustments to be made. Neither isthere any stop necessary, as the operating arm will hit the cup rim ifdepressed too far, the give in the contact springs preventing damage upto that point.

The key as illustrated is particularly adapted to be mounted on theinstrument panel of an open cockpit airplane, fully exposed to theweather. The angle of the operating arm enables the key to be readilyactuated, even with gloves. The key is water and moisture proof whenapplied to such a panel, as when mounted in a vertical position asdescribed, water will run out of the hollow body portion, the shaftholes being well above the bottom (as mounted) of the cavity. Theelectrical contacts are behind the panel, and if desired may be enclosedin a separate covering to prevent sparks from the contact pointsigniting gasoline vapor.

The form of key shown has been proved practical for airplane use asdescribed, particularly as there usually are no convenient horizontalsurfaces upon which to mount a key of the ordi nary type, the instrumentpanel however, being readily reached by the pilot. The key as describedis also ideally adapted to be inserted in various circuits of a tubetransmitter to provide a break-in system, all of the movable contactsand the operating arm being at ground potential.

I claim:

1. A telegraph key comprising in combination, a metal cup having ahollow body portion and a rim, said rim having a face adapted to befastened to a panel, a shaft passing through the opposite walls of saidcup, an operating arm mounted on said shaft within said cup, said armextending coaxially with said body portion to a level adjacent said faceand thereafter changing direction to form an oblique angle with saidface, and contacts mounted on said shaft outside of said cup.

2. A telegraph key comprising in combination, a metal cup having ahollow body portion and a rim, said rim having a face adapted to befastened to a panel, a shaft passing through the opposite wall of saidcup, an operating arm mounted on said shaft within said cup, said armextending coaxially with said body portion to a level adjacent said faceand thereafter changing direction to form an oblique angle with saidface, contacts movable by the motion of said arm mounted on said shaftoutside of said cup, an insulating member mounted on the bottom of saidcup, and stationary contacts carried by said insulating member tocooperate with said movable contacts for making or breaking electricalcurrents.

3. A telegraph key comprising in combination, a metal cup having ahollow body portion and a rim, said rim having a face adapted to befastened to a panel, a shaft passing through the opposite walls of saidcup, an operating arm moimted on said shaft within said cup, said armextending coaxially with said body portion to aflevel adjacent said faceand thereafter changing direction to form an oblique angle with saidface, a resilient member fastened to one end of said shaft, saidresilient member extending on each side of said shaft at right anglesthereto,

a contact point on each end of said resilient member, an insulatingmember mounted on the bottom of said cup, stationary contacts carried bysaid insulating member to cooperate with each of said contact points formaking or breaking electrical currents, and means for resilientlymaintaining one of said contact points and one of said stationarycontacts in contact.

RALPH M. HEINTZ.

